This is a common operation used at multiple places, add a helper
function for it.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
---
 system/memory.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/system/memory.c b/system/memory.c
index 8b84661ae3..a003095632 100644
--- a/system/memory.c
+++ b/system/memory.c
@@ -1559,6 +1559,15 @@ MemTxResult memory_region_dispatch_write(MemoryRegion *mr,
     }
 }
 
+static void memory_region_set_ops(MemoryRegion *mr,
+                                  const MemoryRegionOps *ops,
+                                  void *opaque)
+{
+    mr->ops = ops ?: &unassigned_mem_ops;
+    mr->opaque = opaque;
+    mr->terminates = true;
+}
+
 void memory_region_init_io(MemoryRegion *mr,
                            Object *owner,
                            const MemoryRegionOps *ops,
@@ -1567,9 +1576,7 @@ void memory_region_init_io(MemoryRegion *mr,
                            uint64_t size)
 {
     memory_region_init(mr, owner, name, size);
-    mr->ops = ops ? ops : &unassigned_mem_ops;
-    mr->opaque = opaque;
-    mr->terminates = true;
+    memory_region_set_ops(mr, ops, opaque);
 }
 
 bool memory_region_init_ram_nomigrate(MemoryRegion *mr,
@@ -1710,10 +1717,8 @@ void memory_region_init_ram_device_ptr(MemoryRegion *mr,
 {
     memory_region_init(mr, owner, name, size);
     mr->ram = true;
-    mr->terminates = true;
     mr->ram_device = true;
-    mr->ops = &ram_device_mem_ops;
-    mr->opaque = mr;
+    memory_region_set_ops(mr, &ram_device_mem_ops, mr);
     mr->destructor = memory_region_destructor_ram;
 
     /* qemu_ram_alloc_from_ptr cannot fail with ptr != NULL.  */
@@ -1759,9 +1764,7 @@ bool memory_region_init_rom_device_nomigrate(MemoryRegion *mr,
     Error *err = NULL;
     assert(ops);
     memory_region_init(mr, owner, name, size);
-    mr->ops = ops;
-    mr->opaque = opaque;
-    mr->terminates = true;
+    memory_region_set_ops(mr, ops, opaque);
     mr->rom_device = true;
     mr->destructor = memory_region_destructor_ram;
     mr->ram_block = qemu_ram_alloc(size, 0, mr, &err);
-- 
2.41.3